Replacement Disks for PS4000 or PS6000

san-surfer,

Replacement disks are available from Dell to either fill or upgrade your array. You can not mix disk sizes or types (SAS / SATA) in the array enclosures. The disks used in our array's have been tested to meet certain specifications so it would not be recommended to replace them with just a retail version of the same or larger capacity drive. If you did replace them and something went wrong you are correct Dell would not support nor warranty the units. One nice feature of the EqualLogic array's is the ability to add and remove arrays from the group / pool, while maintaining your data, when your storage needs change.

What is the reason you are looking to change the drives with off the shelf retail disks?

The simple answer is that we have a PS5000 enclosure that has had to have the disks physically destroyed for security reasons. They were SATA 250Gb drives. 16 of them. We still have the caddies and could just buy 16 replacement disks from Dell - but the cost is around $12,000 US dollars. We only want to use this particular enclosure for demos and our test lab. We never want to put production data onto it. $12,000 is a lot of money to spend on a chassis when we could buy in theory a minimum of 8 or 16 disks at $40 a pop absolute tops ! My questions is really a technical one though. Not a commercial one. What is the minimum number of disks you need in an enclosure to boot the SAN up ? if its only a couple, then I am happy to buy orginal Dell replacement / spare disks and then use identical OEM disks from the same vendor (e.g Seagate) to fill up the other slots. Its only for demos so will never have any data of any value on it. Is the SAN firmware stored in flash on the controllers or on the hard disks themselves ? If its the controllers, then any old SATA disks will do for a lab SAN. If the disks are specially adapted by dell for use in the SAN, then I guess I am forced to buy at least a couple of spare replacement disks from Dell. I want to get an accurate answer to this as nowhere in the documentation does it say what the minimum number of disks are, and where the firmware for the SAN lives. Hope someone can answer what is (I would hope) a relatively straightforward question. cheers

Okay understood. You know that this would not be supported and the warranty null, but in theory you could replace the disks with standard SATA disks. 8 is the minimum you would need. The firmware for the controllers does live on the controllers with some data writen to the drives once everything is up and running. Since you are talking about using this for lab / test use, you should be okay. I would in no way put live or production data on this array as the performance and possiable error rate is unknow with this configuration.

Good luck ...

Thanks Lance, that's interesting. I always wondered whether the web/SSH/console management software for the SAN was run from the SAN hard disk array or the controller(s). I've been using equallogic products for 5 years now. I am pleased you have confirmed its on the controller. when you say 'firmware' I'm assuming you mean the SAN sofware is stored on the removeable flash card then on the controller ? Thank you for confirming that a minimum of 8 disks is needed to get the array up and running.

No problem thanks for using EqualLogic, hope this get you going in your lab, but please keep us in mind when you need to add capacity to your production arrays.

Yes firmware is the SAN software and is stored on the removable flash card.

Take care ...